There are several ways to approach the “intermittent” part of food restriction. One of the most common is limiting the window in which food is consumed to about eight hours a day. Another is fasting for a full 24 hours once a week, or once a month. Fasting beyond three days can be stressful on the body and should be done with medical advice and supervision.
Intense exercise — more than just fidgeting or pacing — uses ketones, when glucose is in short supply, which means the body has to create more ketones to replace what you use. This is great for those who are used to a moderate to intense activity level, but intensity is a fine dance between encouraging ketone production and elevating cortisol for the rest of us.
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Hi Acadia, just want to clear up a few things you noted in your post: The manufacture of BHB salts involves ionic bonding of an anion (beta-hydroxybutyrate) with a cation (Na+, K+, Ca+, Mg+). At least one of the exogenous ketone products you listed does in fact contain potassium ions. People taking potassium-sparing drugs need to know this and that raises concerns about leaving it off your chart. Some people are genuinely sodium sensitive even to small amounts of salt added to otherwise healthy foods. This can hold true even for those following ketogenic diets. The term you’re looking for… Read more »
Interestingly, the effects of exogenous ketones on blood substrate concentrations were preserved with the metabolic stimulus of a mixed meal. Following KE drinks, FFA and glucose fell and remained low in both fed and fasted subjects, despite higher insulin throughout the fed arm, suggesting that there was no synergistic effect of insulin and βHB to further lower blood glucose or FFA. In agreement with previous work, the threshold for the effects of βHB on glucose and lipids appears to be low (<1 mM), as there was no significant dose-response relationship between increasing blood βHB and the small changes in plasma FFA, TG or glucose across all of the study drinks (Mikkelsen et al., 2015).
When our cells undergo the process of autophagy, non-essential parts like damaged proteins are recycled and invading microorganisms and toxic compounds are removed. This means that autophagy plays an important role in stopping the aging process, reversing disease, and preventing cancer, but it doesn’t happen all the time. Fasting, protein restriction, and carbohydrate restriction are the three main ways that can initiate different autophagic processes — all of which are not the same. This is part of the reason why a ketogenic diet has so many positive effects, and it also shows you why intermittent fasting is a way to improve your diet even more.

You are probably wondering how there could possibly be a benefit to eating less frequently that goes beyond what you are already getting with a ketogenic diet. Restricting carbs and eating enough fat and protein does come with a plethora of health benefits, but when you add intermittent fasting to your lifestyle you can increase energy and reverse aging by harnessing the power of a nobel prize winning process.

My two cents: I wouldn’t take ketone supps if not on some sort of low(ish) carb diet because the idea of high levels of BOTH fuels (ie, ketones AND glucose) doesn’t seem physiologically appropriate… more like a recipe for disaster, and by “disaster,” I mean “out-of-control production of Reactive Oxygen Species” — this might not matter if you’re an athlete looking for a quick performance boost, because the fuels are going to be cleared rather quickly… not so much if you’re a desk jockey.
The effects of the two exogenous ketone drinks on acid-base balance and blood pH were disparate. In solution the ketone salt fully dissociates (giving a total of 3.2–6.4 g of inorganic cation per drink), allowing βHB− to act as a conjugate base, mildly raising blood and urine pH, as seen during salt IV infusions (Balasse and Ooms, 1968; Balasse, 1979). Urinary pH increased with the salts as the kidneys excreted the excess cations. In contrast, KE hydrolysis in the gut provides βHB− with butanediol, which subsequently underwent hepatic metabolism to form the complete keto-acid, thus briefly lowering blood pH to 7.31. Electrolyte shifts were similar for both KE and KS drinks and may have occurred due to βHB− metabolism, causing cellular potassium influx and sodium efflux (Palmer, 2015).
Recently, two published studies investigated the effects of ketone salts in athletes (total n = 22).8,9 Performance over a four-minute cycling time-trial and a 150 kJ ( ~11 mins) cycling time trial were compared between ketone salts vs. carbohydrate. In the four-minute trial there was no change in performance, and in the 150 kJ test, performance decreased by 7%. Blood BHB levels peaked at 0.6 and 0.8 mM in these studies.
In a keto-adapted individual where ketone metabolism is brisk with up to 100 grams or more being oxidized (i.e., ‘burned for energy’) daily, the small amount lost in breath and urine as acetone is minor. But because this breakdown occurs spontaneously without needing the help of enzymes, it also happens to AcAc in a stored beverage or food (even in an air-tight container), making the shelf-life of AcAc-containing products problematic. Thus all current ketone supplements consist of BOHB in some form rather than the naturally occurring mix of BOHB and AcAc produced by the liver.
Hello, I’ve tried several different Exogenous Ketone supplements and I believe Perfect Keto may be the best I’ve tried. Thus far I’ve had Keto//OS from Pruvitt, Kegenix, KetoForce, KetoCaNa and Ketond. Out of all these brands both Perfect Keto and Ketond have been the products that hack me into Ketosis quick and for longer periods of time. Perfect Keto is less expensive that Ketones from Pruvitt mainly because Pruvitt and their Network Marketing is all about making money. The flavors of Perfect Keto are much better than Pruvitt.
If you have already mastered the Very Low Carbohydrate (VLC) or ketogenic way of eating, and/or are eating at a caloric deficit, exercising or fasting you are naturally creating the optimal conditions for your body to produce ketones and put your body into nutritional ketosis. By strict adherence to a well-formulated ketogenic diet (complete with higher levels of mineral salts) you should be able to produce all the ketones you need naturally (endogenously). If you are new or inexperienced in ketogenic eating however; or if you or a family member struggles to adhere to a ketogenic diet, then supplementation with exogenous ketones may be very beneficial. Not only will ketone supplements help to mitigate hunger and carb cravings, but they will also help you stave off carb flu symptoms (see below), giving you the best possible chance of long-term success.
If given all as a single salt, 50 grams per day of BOHB would mandate daily intakes of 5.8 g Mg++, 9.6 g Ca++, 11.0 g Na+, or 18.8 g K+. Even if divided up carefully as a mixture of these various salts, it would be problematic getting past 30 grams per day of BOHB intake. And again, most of the currently marketed ketone salt formulations are made with a mix of the D- and L-isomers of BOHB, so the actual delivered dose of the more desirable D-isomer is considerably less. The other concern with the salt formulations is that, as the salts of weak acids, they have an alkalinizing metabolic effect that might have a modest but cumulative effect on blood pH and renal function.
I eat one meal a day during a one-hour window and fast 23 or more hours every day. I want to use your ketones to get back into ketosis faster after that meal. Will that work? I am confused, because say at the end of my hour eating window I drink your ketones, sure there are lots of ketones suddenly in my body but I also have a big meal in my stomach. My body has to digest and use that food energy, so how do exogenous ketones help me in that case?

Electrolyte Imbalance – The physiological reasoning behind electrolytes becoming depleted during a state of ketosis is due to lack of water retention and frequent urination. When supplementing with exogenous ketones, the acute state of ketosis will likely increase the frequency of urination, but it won’t deplete glycogen stores. Therefore, it may be useful to drink an electrolyte solution if you are urinating a lot after taking exogenous ketones, but it’s dependent upon how you feel.

The human studies aren’t quite there yet, but it seems likely that they’d help. A recent human case study found that ketone esters added to the regular diet improved Alzheimer’s symptoms. Animal studies indicate that adding exogenous ketones to a regular lab (read: not ketogenic) diet can reduce seizure activity and improve overall symptoms in epilepsy animal models, reverse early neuronal hyperactivity in Alzheimer’s animal models, and reduce anxiety in rats.
Great question. We can’t see any reason this can’t be a part of a successful weight loss program on the ketogenic diet. In the morning with coffee is a very popular way to raise ketone levels in the morning. See if you are on pace with your goals and perhaps try a week with a different breakfast to see what feels best. Also – new article might be helpful here too: https://perfectketo.com/exogenous-ketones-for-weight-loss/ Good luck! 🙂
Disclaimer: While we work to ensure that product information is correct, on occasion manufacturers may alter their ingredient lists. Actual product packaging and materials may contain more and/or different information than that shown on our Web site. We recommend that you do not solely rely on the information presented and that you always read labels, warnings, and directions before using or consuming a product. For additional information about a product, please contact the manufacturer. Content on this site is for reference purposes and is not intended to substitute for advice given by a physician, pharmacist, or other licensed health-care professional. You should not use this information as self-diagnosis or for treating a health problem or disease. Contact your health-care provider immediately if you suspect that you have a medical problem. Information and statements regarding dietary supplements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease or health condition. Amazon.com assumes no liability for inaccuracies or misstatements about products.

I started this website because it was hard to find trustworthy, evidence-based information about the ketogenic diet. Information that was published and peer reviewed by respected scientific journals. After years of research, I'm sure you'll achieve great results in a healthy way following my advice. I do my best to translate scientific research jargon into plain English. Remember, it's always a good idea to consult a doctor before starting a new diet!

Although several studies have linked calcium supplementation with an increased risk of heart attack and heart disease[18], other studies have not found the same association. For example, a study on calcium supplementation (1000 mg/day) in postmenopausal women indicated a reduced risk of hip fracture, but no increase in cardiovascular disease or mortality in the supplement group, compared to the placebo group[19]. Another study found no effect from calcium supplementation (600 or 1200 mg/day) on abdominal aortic calcification[20].
Do I still follow a ketogenic diet? Not anymore. I was strict keto for 12 weeks – enough time to experiment and learn about it. I did enjoy parts (lots of fat!) but I don’t see it as a sustainable way of eating, nor did I benefit from it health or sports performance wise (more on this in an upcoming article). But, I was following a strict keto diet – sans carbs. I think if I were to follow a ketogenic diet AND incorporate a regular carb refeed then the results may be different.

Another factor to consider is that in nutritional ketosis the liver makes a steady supply of ketones and continuously releases them into the circulation. In contrast, most ketone supplement protocols involve bolus intakes that don’t mimic the endogenous release pattern. The extent to which this impacts metabolic and signaling responses across different tissues remains unclear.

You may wonder why we are emphasizing on using these specific oils. Well, this is because the extra virgin oil is an unprocessed form, and contains lauric acid that is antimicrobial in nature and is good for brain health. (This is the same lauric acid that is naturally found in breast milk as well.) Its antibacterial property also indirectly supports the growth of Candida that keep your gut healthy.
There is one viable explanation for consuming ketones. If you're in a calorie or carb-restricted state, then maybe during a workout it would make sense. But even then, that really only applies to endurance activities, since it has more to do with enhancing aerobic performance (where oxygen is required), than it does with enhancing high-intensity efforts (where it's not).

Look around your grocery store, and you’ll soon start to see “Fortified with Calcium” on a variety of different labels, along with calcium supplements everywhere you look. Calcium is essential for cardiovascular health, but several studies have found too much calcium to be associated with cardiovascular events and even death. One study found that consumption of 1000+ mg of supplemental calcium per day was associated with an increased risk of death from cardiovascular disease in men but not women[13]. Dietary calcium intake (i.e., calcium from incorporated foods such as milk, etc.), on the other hand, was not associated with death from cardiovascular disease in men or women. Additionally, a different study found 1000 mg of supplemental calcium to be associated with an increase in rates of cardiovascular events in women[14].

Exercising is undoubtedly important when it comes to losing weight. An added bonus of being in a state of ketosis is the ability to improve your exercise performance, but you should also remember that entering ketosis for the first time can be a bit of a challenge for a lot of people. The body is still adjusting to such a dramatic diet change, so exercising may prove to be difficult at first. The key here is to keep going.
When the results for the supplement and the placebo were within 0.2 (either % or mmol/L) of each other, we classed the supplement as neither “better” nor “worse” than the placebo. We gave a “winning brand” sticker to the brand that scored highest against the placebo for each marker, but not for physical performance, since none of the supplements performed better than the placebo for that marker.
Hi! I have what might be a silly question about using these supplements. What happens if you are taking them and your diet goes off the rails, like you take the Keto//OS and then eat a bunch of pizza or chocolate. Does your body just immediately revert back to using the carbs for energy instead of the ketones? Or, if it doesn’t, would that mean your body would just store those carbs as fat? I realize that ideally you wouldn’t eat the pizza, but sometimes I do and I worry about what exactly I’m doing to my body if I’ve also taken ketones.
We demonstrated that therapeutic ketosis could be induced without dietary (calorie or carbohydrate) restriction and that this acute elevation in blood ketones was significantly correlated with a reduction in blood glucose (Figs. 2, ​,33 and ​and4).4). The BMS ketone supplement did not significantly induce blood hyperketonemia or reduced glucose in the rats. The KE supplemented rats trended towards reduced glucose levels; however, the lower dose of this agent did not lower glucose significantly, as reported previously in acute response of mice [59]. MCTs have previously been shown to elicit a slight hypoglycemic effect by enhancing glucose utilization in both diabetic and non-diabetic patients [86–88]. Kashiwaya et al. demonstrated that both blood glucose and blood insulin decreased by approximately 50 % in rats fed a diet where 30 % of calories from starch were replaced with ketone esters for 14 days, suggesting that ketone supplementation increases insulin sensitivity or reduced hepatic glucose output [89]. This ketone-induced hypoglycemic effect has been previously reported in humans with IV infusions of ketone bodies [90, 91]. Recently, Mikkelsen et al. showed that a small increase in βHB concentration decreases glucose production by 14 % in post-absorptive health males [92]. However, this has not been previously reported with any of the oral exogenous ketone supplements we studied. Ketones are an efficient and sufficient energy substrate for the brain, and will therefore prevent side effects of hypoglycemia when blood levels are elevated and the patient is keto-adapted. This was most famously demonstrated by Owen et al. in 1967 wherein keto-adapted patients (starvation induced therapeutic ketosis) were given 20 IU of insulin. The blood glucose of fasted patients dropped to 1–2 mM, but they exhibited no hypoglycemic symptoms due to brain utilization of ketones for energy [93]. Therefore, ketones maintain brain metabolism and are neuroprotective during severe hypoglycemia. The rats in the MCT group had a correlation of blood ketone and glucose levels at week 4, whereas the combination of BMS + MCT produced a significant hypoglycemic correlation both at baseline and at week 4. No hypoglycemic symptoms were observed in the rats during this study. Insulin levels were not measured in this study; however, future ketone supplementation studies should measure the effects of exogenous ketones on insulin sensitivity with a glucose tolerance test. An increase in insulin sensitivity in combination with our observed hypoglycemic effect has potential therapy implications for glycemic control in T2D [40]. Furthermore, it should be noted that the KE metabolizes to both AcAc and βHB in 1:1 ratio [29]. The ketone monitor used in this study only measures βHB as levels of AcAc are more difficult to measure due to spontaneous decarboxylation to acetone; therefore, the total ketone levels (βHB + AcAc) measured were likely higher, specifically for the KE [14]. Interestingly, the 10 g/kg dose produced a delayed blood βHB peak for ketone supplements MCT and BMS + MCT. The higher dose of the ketogenic supplements elevated blood levels more substantially, and thus reached their maximum blood concentration later due to prolonged metabolic clearance. It must be noted that the dosage used in this study does not translate to human patients, since the metabolic physiology of rats is considerably higher. Future studies will be needed to determine optimal dosing for human patients.

Exogenous ketones can lower appetite during a fast. After an overnight fast, normal weight human subjects either drank a ketone ester supplement or a calorie-matched glucose drink. Compared to the glucose drinkers, the ketone drinkers had lower insulin, lower ghrelin, greater satiety, and less hunger. This can be useful for people trying to extend their fast who don’t want to or can’t yet deal with the hunger. You’re still taking in energy, but the metabolic profile remains similar to that of a fasted person.

In a nutshell… WOW! The chart above shows each of the games/categories I played, showing my prior 5-day averages compared to the day I took the ketone esters. Compared to my baselines, my scores increased across the board, with the biggest improvements in spatial orientation (+32.2%), working memory (+23.7%), quantitative reasoning (21.5%), task switching (+14.9%), and information processing (+14.9%). Below are more detailed comparisons:
Before the Nobel Prize was awarded to Yoshinori Ohsumi, other researchers were making groundbreaking discoveries about autophagy. In 2009, an article was published in Cell Metabolism entitled Autophagy Is Required to Maintain Muscle Mass. In this article, researchers described how deactivating an important autophagy gene resulted in a profound loss in muscle mass and strength.
Personally, I do this on Friday night to Saturday night, so if something happens and my hunger hasn’t crashed by Sunday morning, I have another day that I can go zero carb to keep the momentum going. While the body will trigger ketosis as soon as you run out of glycogen, hunger is attached to your triglyceride and insulin levels, which might take an extra day to normalize.
Hi Mark, sorry this is off topic but not sure where to send a question for a future Ask Mark. I’m about to go into my yearly physical and I am wondering if there is any specific bloodwork that you like to do for your annual check up. I’m 47 year’s old and the than the basic blood work like lipid panel, etc..I’m going to ask my doctor to test my testosterone, HbA1C, fasting insulin, and Vitamin D levels. I’m also going to ask my doctor to do a stool test to check for parasites or other infections I may have picked up from open water swimming for triathlons. Can you recommend any other blood work that might be useful? Thanks!
I don’t recommend that you go straight for a 1-2 day fast, but begin by restricting yourself to certain eating windows. Typically people restrict themselves to the hours of 5pm – 11pm. People often refer to their fasting windows by numbers: 19/5 or 21/3, for example, means 19 hours of fasting and 5 hours eating or 21 hours fasting and 3 hours eating, respectively.

Disclaimer: While we work to ensure that product information is correct, on occasion manufacturers may alter their ingredient lists. Actual product packaging and materials may contain more and/or different information than that shown on our Web site. We recommend that you do not solely rely on the information presented and that you always read labels, warnings, and directions before using or consuming a product. For additional information about a product, please contact the manufacturer. Content on this site is for reference purposes and is not intended to substitute for advice given by a physician, pharmacist, or other licensed health-care professional. You should not use this information as self-diagnosis or for treating a health problem or disease. Contact your health-care provider immediately if you suspect that you have a medical problem. Information and statements regarding dietary supplements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease or health condition. Amazon.com assumes no liability for inaccuracies or misstatements about products.

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Medical Disclaimer: The material on this site is provided for informational purposes only and is not medical advice. Always consult your physician before beginning any diet or exercise program.